From 7ea12d1e6746d9cdf57fb657a015200267649ca7 Mon Sep 17 00:00:00 2001
From: Punya Biswal <pbiswal@palantir.com>
Date: Wed, 15 Apr 2015 19:55:41 -0400
Subject: [PATCH] Handle long args when detecting PID reuse

sbin/spark-daemon.sh used

    ps -p "$TARGET_PID" -o args= to figure out

whether the process running with the expected PID is actually a Spark
daemon. When running with a large classpath, the output of ps gets
truncated and the check fails spuriously.

This weakens the check to see if it's a java command (which is something
we do in other parts of the script) rather than looking for the specific
main class name. This means that SPARK-4832 might happen under a
slightly broader range of circumstances (a java program happened to
reuse the same PID), but it seems worthwhile compared to failing
consistently with a large classpath.
---
 sbin/spark-daemon.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sbin/spark-daemon.sh b/sbin/spark-daemon.sh
index d8e0facb81169..de762acc8fa0e 100755
--- a/sbin/spark-daemon.sh
+++ b/sbin/spark-daemon.sh
@@ -129,7 +129,7 @@ run_command() {
 
   if [ -f "$pid" ]; then
     TARGET_ID="$(cat "$pid")"
-    if [[ $(ps -p "$TARGET_ID" -o args=) =~ $command ]]; then
+    if [[ $(ps -p "$TARGET_ID" -o comm=) =~ "java" ]]; then
       echo "$command running as process $TARGET_ID.  Stop it first."
       exit 1
     fi
@@ -163,7 +163,7 @@ run_command() {
   echo "$newpid" > "$pid"
   sleep 2
   # Check if the process has died; in that case we'll tail the log so the user can see
-  if [[ ! $(ps -p "$newpid" -o args=) =~ $command ]]; then
+  if [[ ! $(ps -p "$newpid" -o comm=) =~ "java" ]]; then
     echo "failed to launch $command:"
     tail -2 "$log" | sed 's/^/  /'
     echo "full log in $log"